The use of ultrasonic energy for combining responsive materials in web-size widths, as in quilting, involves provision of a pattern roll for supporting the material being combined in relation to a series of sonic horns so that the ultrasonic energy is converted to heat at the output surfaces of the horns wherever the pattern roll acts as an opposing anvil. U.S. Pat. No. 3,733,238 illustrates and describes an arrangement of such apparatus. The pattern rolls heretofore available for use in apparatus of this sort have been formed by drilling the roll body to receive pin elements in a particular pattern. When pin elements are installed in this way, however, the process of roll formation is not only particularly tedious, but it is also difficult to maintain the pins at an even projecting height, and it is additionally difficult to secure the pins in place adequately for extended roll use because the sonic horn action generates a severe tendency to vibrate them loose.
The present invention eliminates these difficulties and further allows considerably greater pattern possibilities than prior practice has permitted.